Caligus dasyaticus Rangnekar, 1957
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publication ID |
https://doi.org/ 10.1080/00222930701203853 |
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persistent identifier |
https://treatment.plazi.org/id/0393EE77-FFA6-FFA9-FE06-D732342B741F |
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treatment provided by |
Carolina |
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scientific name |
Caligus dasyaticus Rangnekar, 1957 |
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Caligus dasyaticus Rangnekar, 1957
( Figures 3 View Figure 3 , 4 View Figure 4 )
Material examined
One adult ♀ on body surface of Dasyatis naυarrae (Steindachner) collected on 15 April 2005 at Dong-shi Fishing Port of Chiayi County .
Female
Body ( Figure 3A View Figure 3 ) 5.62 long, excluding setae on caudal ramus. Cephalothoracic shield slightly longer than wide, 2.96X2.78, excluding lateral, hyaline membrane. Fourth pediger slightly wider than long, 0.48X0.58. Genital complex like a wide-mouthed bottle, 1.14X1.04. Abdomen, 0.92X0.54, with wider anterior half; narrow posterior half with central furrow on posterodorsal part ( Figure 3A View Figure 3 ). Caudal ramus ( Figure 3H View Figure 3 ) slightly longer than wide, 0.18X0.16, with narrow base and armed with usual three short and three long plumose setae. Egg sac not seen.
Antennule ( Figure 3B View Figure 3 ) two-segmented; proximal segment carrying on anterodistal surface 24 setose and three naked setae (two dorsal and one terminal), distal segment armed as in C. arii but relatively longer, about 3.7 times as long as wide. Antenna ( Figure 3C View Figure 3 ) three-segmented; first two segments small and unarmed; distal segment long claw with uneven medial margin, one small seta in basal region, and another one at about one-third length from base. Postantennal process ( Figure 3C View Figure 3 ) comprising a long, bent claw with two setule-bearing basal papillae and a bluntly pointed lobe with small subterminal protuberance. Mandible ( Figure 3D View Figure 3 ) as in C. arii . Maxillule ( Figure 3C View Figure 3 ) comprising long, slender dentiform process and tiny basal papilla with two short and one long setae. Maxilla ( Figure 3F View Figure 3 ) essentially as that in C. arii . Maxilliped ( Figure 3G View Figure 3 ) slender as in C. arii . Box of sternal furca ( Figure 3E View Figure 3 ) small, with ear-like projections at base and two slender tines at terminal end.
Armature on rami of legs 1–4 as follows (Roman numerals indicating spines and Arabic numerals, setae):
Exopod Endopod
Leg 1 1-0; III,I,3 (Vestigial)
Leg 2 I-1; I-1; II,I,5 0–1; 0–2; 6
Leg 3 I-1; I-1; III,4 0–1; 6
Leg 4 I-0; III (Absent)
Leg 1 ( Figure 4A View Figure 4 ) protopod protruded laterally and bearing papilla tipped with two setules, also carrying plumose, outer seta and another similar inner seta in addition to a large patch of spinules on ventral surface; vestigial endopod tipped with two tiny setae; first segment of exopod with row of setules on posterior edge and small hyaline membrane at base of short, spiniform, outer seta; middle two of four terminal elements on last segment of exopod bearing long accessory process; fourth element small as in C. arii ; digitiform process on posterior surface close to pectens at base of outer three terminal elements. Leg 2 ( Figure 4B View Figure 4 ) essentially armed and decorated as in C. arii , except for papilla on ventral surface of coxa and basis carrying two tiny setules instead of single, long setule. Leg 3 ( Figure 4C View Figure 4 ) protopod (apron) with short, outer and long, inner seta; marginal membrane on posterior edge of basis except portion with velum; setule-bearing papilla on basis near both ends of inner marginal membrane; pecten on proximal segment of exopod close to insertion of outer spine. Leg 4 ( Figure 4D View Figure 4 ) slender; protopod with small, plumose, outer seta; tip of exopod with two short, outer and one long, inner spines; pecten on exopodal segments at insertion of proximal outer spine and distal inner spine. Leg 5 (inserted drawing in Figure 3A View Figure 3 ) represented by four small, plumose setae on a protuberance located on posterolateral margin of genital complex.
Remarks
Since this species has been reported to occur on the stingrays in India and Japan, it would be expected to be found on the stingray from Taiwan. While the specimen from Taiwan is unquestionably identical with those reported by Rangnekar (1957) from India and Shiino (1960) from Japan, it is noticeably different from that reported by Pillai (1968) from India. The main differences are found in Pillai’s (1968) specimens with (1) the abdomen distinctly longer than the genital complex in the female; (2) the antenna bearing forked (instead of simple) terminal claw in the male; (3) the maxilliped equipped with a robust (instead of slender) corpus in both sexes; and (4) leg 4 tipped with three subequal (instead of distinctly unequal) spines in both sexes. Also, Pillai’s (1968) specimens were obtained from the sawfish ( Pristis ) and not the stingray ( Dasyatis ). Thus, Pillai’s (1968) ‘‘ Caligus dasyaticus ’’ very likely represents a different species. However, without the chance of examining the specimen, we shall refrain from making a formal proposal on the change of the scientific name.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.